Art of trimming cans or the like



Nov. 13, 1951 WI H 2,575,104

v ART OF TRIMMING CANS OR THE LIKE Filed Nov. 4, 1946 34 X fla i l I 23INVENTOR. 24 29 20 6) 51W aiizfiw firm/m.

Patented Nov. 13, 1951 UNITED STATES PATENT V OFFICE 16 Claims.

Thepresent invention relates generally to improve'ments in the art oftrimming the brims of cup-like articles and relates more specifically toan -improved method of and apparatus tor dressingthe raw end edges ofcans or similar articles formed of relatively rigid material.

' The primary object of'my invent-ion is to provide an improved method:of and apparatus for rapidly andreileotively trimming the brims ofrig-idcup-shaped articles formed of sheet metal or other relatively thinsheet-like material.

When cans or other cup-shaped articles. are extruded or drawn from.sheet material so as to provide seamless structures, the brims are ordinari'ly rough and jagged. and must be dressed so as '=to:.provide smoothmarginal edges. Heretoioreit-has been common commercial pra tice to trimitheserawbrim edges of circmar and noncircular cans, by r volving the sucessiv upshaped articles about their central axes and by presenting therevolving brims to cutters, but

this method has proven quite unsatisfactory.

mainly because the side wall distortion caused by rapidly rotating theflexible sheet metal re-, ceptacles prevented accurate trimming andfrequently tore or left burrs and other Waste material upon the canedges. While it has also been proposed to insert successive extruded ordrawn sheet metal seamless cans or the like between dies which snuglyengaged the internal and external surfaces of the cups, and bysubsequently shearing the'raw edges on" with the aid of a revolvingcutter; no proper provision was made With this prior proposal, forrapidly inserting and ejecting the successive cans into and out of theretaining dies without undesirable distortion and alteration in length,so that this method was too cumbersome and tedious for high speedoperation and commercial use.

It is therefore a more specific object of this invention to provide animproved method of trimming circular or non-circular metallic or plasticcans or cups, whereby the articles may be properly dresse'dto accuratedimensions in rapid succession and with minimum waste of material due"to tearing of the thin receptacle stock.

Another specific object of the present invention is to provide simpleand highly efficientapparatus for carrying on the commercialexploitation of :my improved can trimming method.

A further specific-object of my invention is to provide means forfacilitating high speed but, cf: ficient trimming of cans or othercup-shaped articles of diverse sizes and shapes, automatically and withminimum danger of injury to attend? ants, and without side Walldistortion.

Still another specific object of the present invention is to provideimproved .instrumentalities for quickly presenting successive cupeshapedarticles to a constantly revolving cutter for edge trimming purposes,and for immediately theree after ejecting the finished articles awayfrom the zone of cutting without damage.

An additional specific object of the invention is to provide anautomatic can edge trimmer which is simple and compact in construction,and which is moreover highly efficient in operation and flexible :iniitsadaptations.

These and other specific objects and advantages of the invention will beapparent from the following detailed: description.

A clear conception of the several steps and features involved myimprovement, and, of the operation of. a typical. machine adapted toex:- ploit the improved method, may. be had by referring to the drawin aompanyin and form ing a part. of this specification wherein like ref,-ercnce characters des s at th same or similar narts'in thevarious views.

, Fig. 1 is a somewhat diagrammatic part sectional side elevation of atypical can trimmer embodyin my invention, the section being taken alongthe vertical longitudinal central plane of the unit while in the ctortrimm n a can;

' Fig, 21s a fra ment of a similar view of the can trimmer, but showinga trimmed can being elected or d livered away irom the cuttin zone; and

Figifi a transverse vertical section through the assemblage of F taken aon he line B -Land view d in he di tion 03-" t e arrows, Whi th invenion ha mb en show and described he ein as havi g-be n embod d i aypial'can tr mmer o erati g upon {me al ic or plac tic cup-shapedreceptacles having approximately re tan ular ansve s cross-section. it.is n t my desire or intention to unnecessarily limit the scope' ortorestrictthe utility of the improved features vby virtue of this specialembodiment.

Reterring to. the drawing, the typical machine for carrying on theimproved can trimming method and which is shown by way of illustration,comprises in general a base 6- providing a sturdy support for a fixedmember I having one end of a horizontal stud 8 fixedly mounted therein,and being provided with a central opening 9 extending through both themember and the stud; a pulley or sheave I rotatably mounted upon themember I and stud 8 by means of antifriction bearings II, I2 and beingrevolvable at high speed by a V-belt I3 coacting with a peripheralgroove I4 formed in the sheave; one or more knife bladesor cutters I6firmly secured to an end face of the sheave III by means of cap screwsI1, and having sharp cutting edges revolvable about the stud 8 on theside of the pulley remote from the support member I; a stationary plugor core I8 firmly but detachably secured to the opposite or overhangingend of thestud 8 with the aid of clamping screws I9, and being formed toslidably receive and to snugly fit the interiors of seamless drawn cans28 or similar cup-shaped articles; an annular chuck 22 fixedly mountedupon the base 6 so as to surround the.

core I8 and being provided with radially movable clamping jaws 23resiliently urged toward the plug by flexible means 24 such as springsor rubber blocks, and being guided in their movement by bolts 25coacting with guide slots 26 or otherwise; a can chute 28 for conductingthe successive untrimmed cans 20 into positions of alinement with thecore plug I8 upon a stationary supporting block 29 secured to the base 6on the side of the chuck 22 remote from the pulley I3 and member I; aninjecting plunger 30 movable horizontally across the top of the block 29to snugly position the successive cans 20 upon the plug I8 between thechuck jaws 23; a knock-out rod 32 for the finished cans 20, reciprocablewithin the central opening 9 of the member I and stud 8 and beingprovided with a central passage or hole 33 communicable with a source offiuid under pressure such as compressed air; and a finished can ejectingplunger 34 movable horizontally across the top of the block 29transversely of the direction of travel of the injector plunger 30.

The base 6 of the unit may be formed of any durable material and themember I, chuck 22, and block 29 may be firmly secured thereto in anySuitable manner as by welding, and the stud 8 should be rigidly securedto the member I in perfect axial alinement with the sheave I0 so thatthe anti-friction or ball bearings II, I2 will be truly coaxial witheach other at all times. The knives or cutters I6 one or more of whichmay be utilized, should be firmly attached to the driving pulley I0 soas to prevent possible shifting of the cutters relative to theirsupporting sheave, and this sheave Ill may be driven by the belt I3 fromany suitable source of power such as an electric motor, so as to revolvethe knives at high speed. The bearings II, I2 should also be so formedas to prevent possible displacement of the cutters I6 along the axis ofthe machine; and the end of the core plug I8 nearest the pulley II),should be positioned and firmly held by the clamping screws I9 so thatthe cutting edges of the knives will just clear this plug end.

As previously indicated, the plug or core I8 should be formed to snuglybut slidably fit the interiors of the particular cans 28 which are to betrimmed, and the chuck jaws 23 should also be formed to snugly butresiliently engage the adjacent external can surfaces. As shown, theplug I8 and jaws 23 are adapted to coact with approximately rectangularcans of a definite length, but when circular or otherwise shaped longeror shorter cans or cups are to be trimmed, the internal core andexternal jaws may be quickly and conveniently replaced by othercorresponding parts adapted to properly cooperate with the new sizes orshapes of the articles, by merely releasing the jaws retaining bolts 25and removing the jaws 23, and by thereafter releasing the core clampingscrews I9 and removing the plug, or by unscrewing the stud 8 from themember I and subsequently removing the plug I8 from the stud. Theresilient means 24, which may be either springs or rubber blocks, urgethe jaws 23 radialiy toward the central axis of the unit, and should besufiiciently strong and flexible to effect proper clamping of the cans20 while being trimmed, but should not unduly resist admission andremoval of the successive cans 20; and the entering ends of the jaws 23should preferably be rounded as shown so as to properly guide the canedges toward the cutting zone.

The can supply chute;28 may be of any desired and well known typecapable of delivering the successive untrimmed cans 20 upon the block29, either by gravity or otherwise; and the horizontally movable caninjecting plunger 30 may be positively reciprocated in any suitablemanner and properly timed, so that it will positively move thesuccessive untrimmed cups or cans 20 oil of the block 29 into the chuck22 and over the plug I8 into the path of the knives, and will beWithdrawn so as to permit free ejection of the finished cans 20 from thecutting zone. Such removal of the trimmed cans 20 after each cuttingoperation has been completed, may be effected either mechanically alonewith the aid of the knock-out rod 32, or by fluid pressure aloneadmitted through the passage or hole 33 in the rod 32 while the latteris held stationary, or by the combined action of the knock-out rod beingmoved and by the admission of fluid under pressure through the hole 33.

The knock-out rod 32 which snugly but slidably coacts with thelongitudinal central opening 9 formed in the member I and stud 8, may beperiodically reciprocated in any suitable manner by a cam or crankcooperating with its end nearest the member I, and the central fluidconducting hole 33 extends from the can engaging end of the rod 32 to apoint sufiiciently remote from this end to insure proper delivery ofejecting fluid when both mechanical and fluid pressure knockout is beingeffected. The central passage 33 is constantly communicable through aseries of lateral ports 36 with a chamber 31 formed in the member I, andthi chamber 31 is communicable through a pipe 38 and past a valve 39with any suitable source of fluid under pressure such as a compressedair reservoir or pump. The valve 39 is operable by a cam or eccentric 48to admit air or other fluid under pressure to the central passage 33 inthe knock-out rod 32 whenever a can 28 has been properly dressed, andproviding fluid pressure ejection is being utilized either alone or inconnection with mechanical ejection. If no fluid pressure can ejectionis being employed, the cam 40 may be disconnected from its drivingsource; and when no mechanical ejection is being used, the knock-out rod32 may likewise be disconnected from its driving source; but in caseboth types of ejection are utilized,

amps-l both the valve 39 and the rod 32'shouid be periodically actuateda-t properly timed intervals;

The final can removing plunger 34 which'is movable horizontallytransversely 'ofthe direction of movement of the injector plunger 39;and over the top of the can supporting block 29, maybe reciprocated inany-suitable manner and at properly timed intervals,-se as tosimultaneously sweep thesuccessive finally trimmed cans 20 oil of theblock 29 and-to advance the-suocessiveuntrimmed cans which drop upon theblock 2 9 l he suecessive new cans 29 drop by gravity into alinementwith-the plunger 34 whenever the latter has been retracted and a new can29 is being pushed onto the plug it by the other plunger-39. Thesuccessive finished cans 29 may be allowed to drop through an opening 42in the base 6, or they may be otherwise removed,.and it will-be notedthat when the successive untrimmedcans are delivered to the machine bygravity from an upright supply chute 2 9, the can stack is supportedeither by the can removing plunger. 34 during presentation of a new can,or by the supporting block 29 a in Fig. 2 whenever a can is beingtrimmed. The timing of the plungers 39, 34. and of the knock-out devicesmust therefore be such that no interference between parts results, andthe various operations should be (affected automatically and. in rapidsuccession in order to permit high speedand effective trimming of atleast one hundred cans per minute.

While the normal operation of the improved can trimming unit should beapparent from the foregoing detailed description of its construction, ashort resume will be given. When the machine has been properly equippedwith a plug I8 and chuck jaws 23 of suitable shapes and sizes, anduntrimmed cans 29 are being supplied by the can chute 28, the sheave 19may be rotated to revolve the cutters l9 and the mechanisms foractuating the knock-out rod 32, the plungers 39, 34 and the valve 39should be set in motion. The injector plunger 39 will then push each ofthe successive cans 29 which are deposited upon the block 29 over thefixed plug or core l8 and between the jaws 29, thereby causing the roughbrims or edges of the cans 29 to enter the path of revolution of theknive 19. As these can edges advance into the cutting zone, they aresheared off in helical formation until the bottom surface of each canengages the adjacent end of the plug l8 and the can motion is arrested,whereupon the trimming operation will have been completed. The snugfitting core l9 insures smooth finishing at the brim edge of each can29, and prevents undesirable distortion of the cans, and the sharprevolving cutters l9 gradually slice off the excess material withouttearing or burring the edges. I

After a out has been completed, the injector plunger 39 is promptlywithdrawn, and immediately thereafter the knock-out devices areactuated. If mechanical removal is utilized alone, no fluid underpressure is admitted through the passage 33 in the knock-out rod 32, butthis rod is merely moved toward the finished can 29 and pushes thelatter off of the plug I9 onto the block 29 and toward the retreatingplunger 39. If fluid pressure removal is employed alone, the knockoutrod 32 will not be moved, but will remain in the position shown in Fig.1, while the valve39 will be actuated by the cam 49 to admit fluid underpressure from the source through the pipe 38, chamber 3i, ports 39 andpassage 33 to the can interior, thereby likewise shifting the finishedcan off of the plug 18 and :onto the block 29 toward the retreatingplunger 39. In cases where both mechanical and fluid pressure removal isdesired, both the knock-out rod 32 and the valve 39 will be actuatedsimultaneously, thereby obtaining joint action during ejection of thecompleted cans 29 from the cutting zone.

When the successive finished cans 29 have been conipletelyremoved fromthe plug I8 and chuck jaws 23, the valve 39 should be closed, and therod '32 should be quickly withdrawn from within each can, whereupon thefluid under pressure will escape from the can interior, and the finalejector plunger 34 may be actuated to sweep the finished articles fromthe block 29. Aftereach such final delivery'of a completed can 29, theplunger 34 will be quickly withdrawn to permit the lowest unfinished can29 in the chute 28 to drop into properposition upon the clearedsupporting block 29, and the previously finished cans 29 will dropthrough the opening 92, while the plunger 39 again becomes active topromptly inject the new properly positioned can into the cutting zone.The successive steps of the improved method are thus quickly andautomatically repeated so as to accurately and effectively trim the cans2 9 "in rapid succession.

From the foregoing detailed description of the construction andoperationof the unit, it will be apparent that my invention provides an improvedmethod of and apparatus for rapidly and effectively trimming cans orother cup-shaped receptacles, without distorting or otherwise damagingthe articles. The invention is applicable to cans or other receptaclesof various sizes and shapes, formed of metal, plastic, stiff paper, orother sheet-like material, and the improved mechanism i adapted toautomatically perform the successive steps of the method both positivelyand safely. Either mechanical removal, or fluid pressure ejection, orboth types of knock-out may be utilized at the will of the operator; andwhile the unit is extremely simple and compact in construction, it stillhas enormous capacity and 'requires minimum attention. The invention hasgone into highly successful and satisfactory "commercial use, and isobviously very flexible in its adaptations; and the improved units maybe manufactured and operated at moderate cost for diverse uses.

It is also noteworthy that the various parts of the improved mechanismshould be formed of suitable wear-resistant materials and properlylubricated so as to insure long life, and the ends of the plugs 18nearest the knives it may be hardened or faced with a hardened plate soas to guard against excessive wear, while the antifriction or ballbearings also reduce the power consumption to a minimum. It should alsobe apparent that any other method of feeding the untrimmed cans onto theblock 29 may be utilized, as for example, the well-known type of curvedcan chute 28 which delivers the cans 29 laterally onto thesupportingblock 29 and causes the newly presented cans to push the finished cansoff of this block, thereby eliminating the use of the plunger 34. Theuse of the plunger 36 for simultaneously removing the finished cans 29and for presenting or positioning the new cans in proper alinement withthe plug I8, however insures perfect positioning of the successivereceptacles in line with the feed plunger 39, thereby assuring reliablefunctioning or performance of the mechanism at high speed. Suchmodifications-of unimportant parts-of the mechanism are obvious to thoseskilled in the art, but the helical shearing of the excess metal at thecan brims by feeding the cans gradually into the path of the rapidlyrevolving cutters is an important feature which has contributed to thesuccess of my invention.

It should be understood that it is not desired t limit this invention tothe exact details of construction or to the precise steps of the method,herein shown and described, for various modifications within the scopeof the appended, claims may occur to persons skilled in the art. It isalso contemplated that specific terms used herein be given the broadestpossible interpretation consistent with the objects and purposes of theinvention, and that the term can shall include any cup-shaped or tubularreceptacle formed of any material.

Iclaim:

1. In a can brim trimmer, a fixed core formed to snugly engage theinterior of a can, means for sliding the can axially along said core inone direction, a cutter revolvable about the can axis and cooperatingwith said core to shear excess stock from the brim edge of the can, andmeans for positively moving the trimmed can in the opposite direction toremove it from said core.

2. In a can brim trimmer, a fixed core formed to snugly engage theinterior of a can and having a plane end surface, means for sliding thecan axially along said core toward said surface, and a cutter revolvableabout the can axis and cooperating with said core to helically shearexcess stock from the brim edge of the can and to provide a final brimedge lying in the plane of said surface, said core acting as a stop toarrest the sliding motion of the can.

3. In a can brim trimmer, a fixed core formed to snugly engage theinterior of a can, means for sliding the can axially along said core, acutter revolvable about the can axis and cooperating with said core tohelically shear excess stock from the brim edge of the can, and meansextending into the can through said core for removing the can from thecore when all excess stock has been removed.

4. A can brim trimmer comprising, a stationary core formed to snuglyengage the internal brim portions of the cans, means cooperable with theexternal bottom surfaces of the cans for advancing the latter axiallyalong said core, a cutter revolvable in close proximity to one end ofsaid core and being cooperable with the brim edges of the advancing cansto helically shear excess stock from said edges, and means resilientlyengaging the exteriors of the cans during said advancement.

5. A can brim trimmer comprising, a stationary core formed to snuglyengage the internal brim portions of the cans, means cooperable with theexternal bottom surfaces of the cans for advancing the latter axiallyalong said core, a cutter revolvably in close proximity to one end ofsaid core and being cooperable with the brim edges of the advancing cansto helically shear excess stock from said edges, means extending throughthe path of revolution of said cutter and cooperating with the internalbottom surfaces of the cans to remove the latter from said core, andmeans resiliently engaging the exteriors of the cans during saidadvancement.

6. A can brim trimmer comprising, a fixed core, means for sliding cansalong said core in one direction, a cutter revolvable about the centralaxis of said core, and means for sliding the cans in the oppositedirection alongsaid core, said last mentioned means extending throughthe path of revolution of said cutter and through said core.

7. A can brim trimmer comprising, a stationary member having a studprojecting therefrom, a cutter revolvably suspended from said member andsaid stud, a core mounted upon the overhanging end of said stud, andmeans for slidably advancing successive cans along said core and forpresenting the brim edges of said cans to the action of said cutter.

8. A can brim trimmer comprising, a stationary member having a studprojecting therefrom, a cutter revolvably suspended from said member andsaid stud, a core mounted upon the overhanging end of said stud, andmeans for slidably advancing successive cans along said core and forpresenting the brim edges of said cans to the action of said cutter,said core being fixed against rotation and coacting with said cutter andwith the cans to positively limit the extent of removal of stock fromsaid cans.

9. A can trimmer comprising, a core formed to snugly engage the internalbrim portion of the can and having a plane end, a revolving cutterhaving a shearing edge cooperable with the plane end of said core, andmeans for advancing a can along said core so as to cause the can brim togradually enter the zone of action of said cutter and to thereby removeexcess brim stock with a helical cut terminating in the plane of saidcore end.

10. A can trimmer comprising, a stationary can receiving core, arevolving cutter cooperable with one end of said core, means for pushingcans onto said core with the can brims advancing into the zone of actionof said cutter, and knockout means extending through said zone and saidcore for ejecting the trimmed cans from the core.

11. A can trimmer comprising, a stationary can receiving core, arevolving cutter cooperable with one end of said core, means for pushingcans onto said core with the can brims advancing into the zone of actionof said cutter, and a knock-out rod movable through said zone and saidcore and being cooperable with the internal bottom surfaces of the cansto eject the latter from said core.

12. A can trimmer comprising, a stationary can receiving core, arevolving cutter cooperable with one end of said core, means for pushingcans onto said core with the can brims advancing into the zone of actionof said'cuttter, and means for delivering fluid under pressure throughsaid zone and said core to the interiors of the cans to eject the latterfrom the core upon completion of each trimming operation.

13. A can trimmer comprising, a stationary core, a chuck surroundingsaid core, a cutter revolvable adjacent to an end of said core, meansfor pushing successive cans along said core within said chuck and intothe zone of action of said cutter, and means extending through said zoneand said core for removing the successive trimmed cans from within saidchuck.

14. A can trimmer comprising, a stationary can receiving core, a chuckhaving jaws resiliently urged against the exterior surfaces of the canswhile coacting with said core, means for feeding cans onto said corebetween said jaws, and a cutter revolvable adjacent to an end of saidcore and coacting with the can brims while the cans are prevented fromrotating by said core and jaws.

15. A can trimmer comprising, a fixed core formed to snugly but slidablyengage the can interiors, a chuck having jaws resiliently contacting theexteriors of cans while being advanced along said core to positivelyprevent rotation of said cans, a cutter revolvable at one end of saidcore, and means for feeding the cans along said core between said jawsand toward the zone of action of said cutter.

16. A can trimmer comprising, a stationary can supporting core having aplane end, a cutter having a shearing edge revolvable in the plane bfsaid core end, means for sliding a can in one direction along said corewith the can brim approaching said plane to cause said shearing 15 edgeto remove excess brim stock from the can,

and means for ejecting the trimmed can from said core in the oppositedirection.

MICHAEL HALOWICH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS 10 Number Name Date 440,548 Elmore et a1. Nov. 11,1890 1,008,784 Cahill Nov. 14, 1911 1,582,973 Dodd May 4, 1926 1,605,924Dodd Nov. 9, 1926 2,232,021 Calleson et a1 Feb. 18, 1941 2,234,330Zetzsche et a1. Mar. 11, 1941

